Instead, the most extraordinary city that man had ever laid eyes upon
was stretched directly beneath. It was grouped about what seemed to be
the meeting-point of three great roads, which led to this spot from as
many passes through the surrounding hills. And the city seemed thus
naturally divided into three segments, of equal size and shape, and each
with its own street system.

For they undoubtedly were streets. No metropolis on earth ever had its
blocks laid out with such unvarying exactness. This Mercurian city
contained none but perfect equilateral triangles, and the streets
themselves were of absolutely uniform width.

The buildings, however, showed no such uniformity. On the outskirts of
this brilliantly tan mystery the blocks seemed to contain nothing save
odd heaps of dingy, sun-baked mud. On the extreme north, however, lay
five blocks grouped together, whose buildings, like those in the middle
of the city, were rather tall, square-cut and of the same dusty, cream-
white hue.

"Down-town" were several structures especially prominent for their
height. They towered to such an extent, in fact, that their upper
windows were easily made out. Apparently they were hundreds of stories
high!

Here and there on the streets could be seen small spots, colored a
darker buff than the rest of that dazzling landscape. But not one of the
spots was moving.

"We'll go down further," said the engineer tentatively, in a low tone.
There was no comment. He gradually reduced the repelling current, so